Gravity lock



March 25, 1924. 1,487,967

J. B. MILTON GRAVITY LOCK Filed May 23, 1925 2 Sheets-Sheet 1' mvzm'oRJoseph 5.0168107? Lucc'le UTMiton, adminstratrdx of 5 Ole estate of J05..B-Millan deceased ATTORNEY WITNESS:

March 25, 1924; 1,487,967

J. B. MILTON GRAVITY LOCK Filed May 23, 1923 2 Sheets-Sheet 2 iNVENT'ORJ05 epn. B.Mc'8 ton Lucile V-Mdlion, Qdvmnd strairx of the es ate ofJos.

Patented Mar. 25, 192

JOSEPH 353. MILTON, DECEASED, LATE OF ENXID, OKLAHOMA; BY LUGIL'E V.IJZILTGELY, ADMINISTRATRIK, OF ENID, OKLAHOMA.

GRAVITY LOCK.

Application filed May 23, 1923.

To all whom aa uay concern:

Be it known that JOSEPH B. MILTON, deceased, a citizen of the UnitedStates, residing at Enid, in the county of Garfield and State ofOklahoma, has invented new and useful Improvements in Gravity Locks, ofwhich the following is a specification.

This invention relates to improvements in looks and has for an objectthe provision of a gravity lock which is especially adapted for lockingrailway switches, the present invention being an improvement upon patentnumbered 1,447,144, granted to me February 27, 1923.

Another object of the invention is the provision of a simple andpositive lock for this purpose which cannot be operated to release theswitch without the use of a special key, so that tampering with theswitch by un authorized persons will be prevented.

With the above and other objects in view, the invention further includesthe following novel features and details of construction, to behereinafter more fully described, illustrated in the accompanyingdrawings and pointed out in the appended claims.

In the drawings Figure 1 is an elevation showing a fragmentary portionof a switch stand with the invention applied thereto.

Figure 2 is a plan view of the same.

Figure 3 is an enlarged vertical sectional view through the lock showingthe operating arm in switch locking position.

Figure 4 is a similar view showing the arm in unlocked position.

Figure 5 is a horizontal section on the line 5-5 of Figure 3.

Figure 6 is a vertical section taken substantially on the line 6-6 ofFigure 3.

Figure 7 is a detail perspective view of one of the tumblers.

Referring in detail to the drawings wherein like characters of referencedenote cor responding parts, the reference character 10 indicates aswitch stand which supports a pivotally movable housing 11, the latterbeing movable over a plate 12 and connected to a switch operating meansby a shaft 13. This shaft passes through and engages the rectangularwalls of an opening 14: and may carry at its upper end a signal orindicating element 15.

Pivotally mounted within the housing 11 as shown at 16 is an operatingarm 17, the

Serial No. 11,021.

latter being adapted when swung downward to the position shown in Figure1, to engage either one of a pair of notches 18, the said notches beingdisposed at 90 degrees with respect to one another. When the arm 17 isengaged with the notches 18, the switch will be held in either open orclosed position, depending upon the particular notch engaged.

Located within the housing 11 is a pair of tumblers 19 and 20, the firstmentioned tumbler surrounding a stud 21 and being provided with a sleeveextension 22, while the tumbler 20 is pivotally mounted upon the sleeveextension 22 and is capable of movement thereon independently of thetumbler 19. The tumblers are thus pivotally mounted so that when theoperating arm is in the position shown in Figure 3 one of their endswill drop by gravity into the path of the said arm and lock the samewithin one of the notches 18.

Pivotally mounted within the housing above the tumblers as shown at 23is what may be termed a locking plate, the said plate being indicated at24-. This plate is substantially triangular and is provided at one endwith an offset shoulder 25 which is adapted to engage a pin 26projecting from one face of the tumbler 20, thus when the tumbler. 20 ismoved pivotally in a direction away from the arm 17, its movement willbe limited so that it cannot entirely move out of the path of this arm.

The tumbler 20 and the sleeve 22 are provided with arcuate recesses 27and 28 respectively which are adapted to receive the bit of a key, whilethe plate 2 1 is provided with a notch 29 which receives the stud 21 andprovides a key bit engaging portion 30. This portion 30 is arrangedsubstantially central between the ends of the recesses 27 and 28 so thatthe bit of the key will first engage this portion 30 and move the platepivotally before any movement is imparted to the tumblers. Continuedmovement however will cause this bit to engage the ends of the recesses,but before this occurs, the plate will have been sufficiently moved tobring the open end of the notch 31 into position to receive the pin 26so that continued movement of the plate will also move the tumblers to aposition out of the path of the arm 17 The latter may then be movedpivotally past the curved edges 32 of the tumblers 19 and 20. Duringthis movement the arm 17 will engage a'dog 33 which is pivotally mountedupon a pin 34. One end of this dog engages one end of each of thetumblers l9 and 20 and when the dog is moved to the position shown inFigure 4.- of the drawings by the operation of the arm 17, the said dogwill hold the tumblers out of the path of the said arm until the latterhas been returned to its switch locking position.

In order to prevent the insertion of a tool or instrument upward withinthe housing 11 to operate the locking plate 24, the dog 20 is providedwith a longitudinally extending laterally ofi'set portion 35 whichextends over the edge of the dog and acts to protect the same.

The invention is susceptible of various changes in its form, proportionsand minor details of construction and the right is herein reserved tomake such changes as properly fall Within the scope of the appendedclaims.

Having described the invention what is claimed is 1. A switch lockcomprising in combination with a pivotally mounted operating arm, a keyoperated pivotally mounted tumbler having one end normally disposed inthe path of movement of said arm, a

key operated pivotally mounted lockingv plate, interlocking meansbetween the tumbler and plate to limit the range of movement of saidtumbler, means whereby the plate may be independently moved to increasethe range of movement and permit the tumbler to be moved out of the pathof the operating arm and means engaged by the operating arm to hold thetumbler in an inactive position.

2. A switch lock comprising in combination with a pivotally mountedoperating arm, a key operated pivotally mounted tumbler having one endnormally disposed in the path of movement of said arm, a key operatedpivotally mounted locking plate, interlocking means between the tumblerand plate to limit the range of movement of said tumbler, means wherebythe plate may be independently moved to increase the range of movementand permit the tumbler to be moved out of the path of the operating armand a pivotally mounted dog having one end engaging the tumbler and theother end arranged for engagement by the arm tohold the tumbler in aninactive position.

3. A switch lock comprising in combination with a pivotally mountedoperating arm, a pair of concentrically pivoted inde pendently movablekey operated tumblers having one of their ends normally disposed in thepath of movement of said arm, a key operated pivotally mounted lockingplate, interlocking means between one of the tumblers and the plate tolimit the range of movement of said tumbler means whereby the plate maybe independently moved to increase the range of movement of theinterlocked tumbler and permit of the tumblers being moved out or thepath of the operating arm and means engaged by the operating arm to holdthe tumblers in an inactive position.

4. A switch lock comprising in combination with a pivotally mountedoperating arm, a key operated pivotally mounted tumbler having one endnormally disposed in the path of movement of said arm, a key operatedpivotally mounted locking plate, a pin carried by the tumbler, ashoulder provided upon the plate and engaging the pin to provideinterlocking means .between the tumbler and plate and limit the range ofmovement of said tumbler, means whereby the plate may be independentlymoved to increase the range or" movement and permit the tumbler to bemoved out of the path of the operating arm and means engaged by theoperating arm to hold the tumbler in an inactive position.

5. A switch lock comprising in combination with a pivotally mountedoperating arm, a key operated pivotally mounted tumbler having one endnormally disposed in the path of movement or said arm, a key operatedpivotally mounted substantially triangular locking plate having a notchin one edge thereof, a shoulder provided on the plate adjacent thenotch, a

pin carried by the tumbler and engaging ture.

7 LUCILE V. MILTON. Admim'stmtm'w for the estate of Joseph B.

Milton, deceased.

